Identification of biomarkers for psychiatric disorders would provide a significant advance in the diagnostic procedure, which is currently dependent on the presentation of clinical symptoms over an extended period of time. Since disorders such as schizophrenia and bipolar disorder are also highly heritable disorders, current pursuits of biomarkers for these disorders have focused on gene-based biomarkers, such as mRNA expression levels. Previous gene expression biomarker studies have identified candidate genes now implicated (though none universally) in the etiology of schizophrenia and bipolar disorder. While some of these candidates are in keeping with previous cellular and molecular studies of psychiatric disorders (Mimics et al. 2001; Vawter et al. 2002; Chen and Chen 2005), novel candidates are also being identified. For example, using microarray analysis, the expression of selenium binding protein 1 gene (SELENBP1) was increased in the blood and brain of patients with schizophrenia (Glatt et al. 2005; finding confirmed in blood using quantitative real-time PCT (QPCR)).